Audi is expanding its engine lineup with a new, high-performance gasoline engine. The 4.0 TFSI, which is used in slightly different configurations in the S6, S6 Avant, S7 Sportback and S8, develops between 309 kW (420 hp) and 382 kW (520 hp), and as much as 650 Nm (479.42 lb-ft) of torque. The new V8 is a high-tech engine featuring numerous innovative solutions.
The youngest member of the large Audi family of V engines, the 4.0 TFSI shares all of their typical characteristics. It has the classic cylinder angle of 90 degrees, the chain drive for the four camshafts and ancillary units is on the back to save space, and the cylinder case is a cast aluminum-silicon alloy. This eight-cylinder unit is very light in weight, and its highly compact construction has resulted in its length being reduced to 497 mm (19.57 in).
Fuel is provided via Audi’s FSI direct injection system. Switchable flaps in the intake ports induce a rolling type of movement in the incoming air for improved combustion. Like almost every Audi engine, the new 4.0 TFSI also follows the principle of downsizing, where forced induction replaces displacement. One turbocharger per cylinder bank compresses the intake air. This is known as twinscroll technology, where the exhaust flows to the turbine wheel at high speed through two separate ports and enables torque to be developed extremely early, just above idle.
